我在UI
ImageView(self.myImage)中有一个透明的png,我想围绕它的中心点旋转.
代码应该非常简单:
代码应该非常简单:
- [self.myImage.layer setAnchorPoint:CGPointMake(0.5,0.5)];
- [UIView animateWithDuration:1.0 animations:^{
- [self.myImage setTransform:CGAffineTransformMakeRotation(angle)];
- }];
图像以正确的速度/时间和直角旋转,但其位置会发生偏移.这是一个正在发生的事情的例子:
灰色方块只是为了在屏幕上显示位置.透明的png(包含在UIImageView中)是另一个图.白色虚线显示UIImageView的中心.图像的左侧显示图像的原始位置,右侧显示使用上述代码旋转后的图像(向右移动一点).黑色和白色圆圈位于图像文件的中心.
有什么东西我不见了吗?据我所知,上面的第一行不是必需的,因为这些是默认值.我是否必须在故事板中以编程方式设置/取消设置某些内容?
解决方法
你只需要尝试这个代码
- - (void)viewDidLoad
- {
- [super viewDidLoad];
- CATransform3D transform = CATransform3DIdentity;
- transform.m34 = -1 / 500.0;
- transform = CATransform3DRotate(transform,.0 * M_PI_2,1,0);/*Here the angle of transform set (Here angle set as 0)*/
- self.transformView.layer.transform = transform;
- }
- - (void)viewWillAppear:(BOOL)animated {
- [super viewWillAppear:animated];
- CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
- animation.fromValue = [NSNumber numberWithFloat:0];
- animation.toValue = [NSNumber numberWithFloat:2 * M_PI];
- animation.duration = 3.0;
- animation.repeatCount = HUGE_VALF;
- animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
- [self.discView.layer addAnimation:animation forKey:@"transform.rotation.z"];
- }
- - (void)viewDidDisappear:(BOOL)animated {
- [super viewDidDisappear:animated];
- [self.discView.layer removeAllAnimations];
- }
- - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
- {
- return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
- }
在这里,您只需使用另一个视图或ImageView更改transformView